The conventional organic solvents used in electrolytes for rechargeable lithium batteries include cyclic esters such as ethylene carbonate and propylene carbonate; chain esters such as dimethyl carbonate and propionic ether; and cyclic ethers such as tetrahydrofurane. However, the conventional organic solvents easily decompose during oxidation and reduction of the battery, or they exhibit poor cycle life characteristics.
Recently, attempts have been made to add organic fluorine-included ethers to the organic solvents in electrolytes, which do not decompose during oxidation and reduction of the battery. The organic fluorine-included ethers have a high fluorine content which results in improved stability during the decomposition, but they are not very compatible with other organic solvents used in the electrolyte.